Welcome to the Magical Mystery Tour, where there's little magic and heaps of mystery.
On opening the double-pack (single-cassette), I suspected Death Or Glory was a budget-price game (at best) bumped up to full price with the level of documentation you'd only expect for something as complex as, say, noughts and crosses. The insert was blank on the inside and the story on the back was less informative than an election manifesto. And yes, talking to CRL's PR dept confirmed my worst tears - this was indeed an £8.95 game and the version I had was the same as the one you'll find in the shops.
With a joystick (the keys are awkward and not redefinable) I found that forward is thrust, back is brake and the fire button, while nothing actually gets fired, needs to be pressed to destroy each piece of the mothership, netting a cool 1000. But colliding with the pesky aliens (the only way to destroy them and often ineffective) gives you a paltry 200+ score.
Since you can rarely avoid their missiles, your shields don't last very long, although as I managed to clock the game on my second attempt, even the most recent convert to gaming should perform respectably on this one!
Be warned that without a Kempston interface on a 48K Speccy, the ship behaves rather erratically (especially when entering high scores). Oh yes, and the game's total rubbish!
A mega-flop if ever there were one. Leave well alone, and ignore this warning at your peril!